SM8136A Datasheet, PDF (1/15 Pages) Nippon Precision Circuits Inc – White LED Driver IC

SM8136A
White LED Driver IC
OVERVIEW
The SM8136A is a charge pump type white LED driver. It can drive 1 to 3 backlight white LED connected in
parallel, making it ideal for portable devices with small LCD. The charge pump switches between ×1 bypass
mode to ×1.5 boost mode in response to LED drive current requirements. The boost switching occurs in
response to the drive current of all the connected LED and thus supports variations in LED forward-bias volt-
age drop (VF). Besides, the detection of switching is repeated in approx. 1sec-cycle by mode reset action, the
SM8136A can respond to temporary variation of supply voltage. These ingenuities on switching detection can
prolong the battery life to the fullest extent. Each LED drive current is controlled by a 3-channel LED drive
current control circuit.
FEATURES
I Battery life extension by automatic charge pump
switch between ×1 to ×1.5 according to the detec-
tion of the LED drive current
I Controlling 1 to 3 lights of white LED connected
in parallel
I 1-wire input controlling
I ON/OFF and brightness control by signal control-
ling of EN pin
I Soft start circuit built-in
I Input voltage range
No-load current (I_OUT = 0mA): 2.7 to 4.6V
Load current (I_OUT = 60mA): 3.0 to 4.6V
I Maximum output voltage: 5.0V (typ)
I Maximum output current: 60mA (typ)
I Quiescent current
Not-switching (×1 mode): 0.3mA (typ)
Switching (×1.5 mode): 1.0mA (typ)
I Standby current: 0.01µA (typ)
I Operating frequency (boost mode): 1.0MHz (typ)
I LED drive current accuracy between channel:
± 5.0%
I Package: 12-pin QFN
APPLICATIONS
I Cellular phone
I PDA
I Portable games
I Portable audio equipment
I Handy terminal
I Digital still camera
I Digital video camera
I LCD panel back light
I White LED driving
PINOUT
(Top view)
NC
GND
VIN
EN
VOUT
C1P
PACKAGE DIMENSIONS
(Unit: mm)
Top view
2.00 ± 0.07
A
B
Bottom view
1.00
0.40 × 2 = 0.80 ± 0.05
12
1
0.10 S A B
0.10 S
S
8−C0.08
0.60
12
C0.30
1
0.18 ± 0.05
φ0.05 M
SAB
0.05 S
0.40
ORDERING INFORMATION
Device
SM8136AB
Package
12-pin QFN
SEIKO NPC CORPORATION —1